1. Field of the Invention
This invention relates to a curable resin composition. More particularly, it relates to a curable resin compositon comprising a grafted primary amino group-containing polymer and a dialkyl oxalate.
2. Description of the Prior Art
Heretofore, as curable resin compositions, the curable resin compositions comprisnig a polyhydric alcohol compound such as polyester polyol or acryl polyol and a polyisocyanate compound and the curable resin compositions comprisnig a polyamine compound such as polyamine or polyamideamine and a polyepoxy compound have been used in various applications involving coating materials, adhesive agent, surface-treating agents, shaped articles, and foam resins. JP-A-61-23,615(1986) discloses a Michael addition type curable resin composition comprising apolyamine compound such as polyamine or polyamideamine and a polyacryloyl group and U.S. Pat. No. 4,414,250 discoses a curable resin composition comprising a polyamine compound and a dialkyl oxalate.
The curable resin compositions which comprise a polyhydric alcohol compound and a polyisocyanate compound feature prominence in reactivity, weatherability, versatility, etc. and yet entail the problem of toxicity of the isocyanate compound, the problem of basic unusableness of the composition in an aqueous system due to ready reactivity thereof with water, and the problem of management of the isocyanate compound for curbing the possible secondary reaction of the isocyanate compuond with water or moisture even when the composition is used in a solvent system or a nonsolvent system. These problems remain yet to be solved. The curable resin compositins which comprise a polyamien compound and epoxy resin feature prominence in reactivity, resistance to chemicals, versatility, etc. and yet entail the problem of deficiency in weatherability, low-temperature curing property, etc. The Michael addition type curing resin compositions which comprises a polyamine compund and a polyacryloyl group excel in low-temperature curable property, weatherability, etc. and yet entail the problem of deficiency in resistance to chemicals, gloss, etc. The curable resin compositions which comprise a polyamine cmopound such as polyamine or polyamideamine and a dialkyl oxalate suffer from the problem of slowness of the rise of the molecular weight of the composition due to the reaction between an oligomer and a monomer and the attendant problem of slowness of the manifestatin of stated physical properties. To eliminate the effects of these problems, curable resin compositions which comprise a dialkyl oxalate and a polyamine compound obtained by modifying with a polyamine a copolymer between a copolymerizable acid anhydride such as maleic anhydride and other copolymerizable monomer has been propsed. These curable resin compositions entail the problem of slowness of the manifestation of stated physical properties due to the failure of the acid anhydride group-containig copolymer to exhibit a sufficient rise in the conversion and also the problem of slowness or incompleteness of the curing reaction due to the formation of an inner salt with the residual carboxyl group.
An object of this invention, therefore, is to provide a novel curable resin composition.
Another object of this invention is to provide a curable resin compositon which is free from the problems observed, as described above, in the curable resin compositions comprisnig a polyhydric alcohol compound anda polyisocyanate compound, the curable resin compositions comprisng a polyamine compound and epoxy resin, and the Michael addition type curable resin compositions comprisnig a polyamine compound and a polyacryloyl group.